One Health perspectives on veterinary residues and bioaccumulation in marine mussels

The increase in pharmaceutical residues and environmental contaminants, including heavy metals and biotoxins, in coastal ecosystems represents a critical threat to global health. Mussels (Mytilus spp.), as sessile filter feeders, serve as primary bioaccumulators and biological indicators of this chemical pressure, yet their toxicological role in human health is often underestimated. This review explores the physiological and toxicological effects of the accumulation of complex contaminants and pharmaceutical residues, specifically including veterinary drugs that reach the marine environment through livestock runoff and aquaculture practices. Mussels' reduced metabolic capacity, combined with the interference of multixenobiotic resistance (MXR) efflux systems, leads to the prolonged accumulation of these substances within their tissues. Particular attention is given to mixture toxicity and the role of microplastics as vectors that amplify the bioavailability of contaminants, triggering significant oxidative stress and epigenetic alterations that compromise the reproduction and resilience of the mollusk. The implications for public health involve the potential facilitation of antimicrobial resistance (AMR), driven by the bioaccumulation of both human and veterinary antibiotics. dietary exposure to chemical residues; however, the actual risk of poisoning depends on whether tissue concentrations exceed established regulatory safety thresholds. Due to their high filtration capacity, mussels act as ecological hotspots, facilitating the transfer of pharmaceuticals and their metabolites into the food chain. We conclude that effective risk management requires a proactive approach at the source. The urgent integration of surveillance protocols with molecular ecotoxicology, alongside the adoption of advanced technological solutions, such as tertiary wastewater treatment and the monitoring of watersheds adjacent to livestock farming areas, are essential to harmonize residue limits and ensure food security and the sustainability of marine resources for future generations.